Securities (Schedule of Securities by Contractual Maturity) (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Amortized Cost
Due in one year or less	$ 3,913
Due after one year through five years	17,534
Due after five years through ten years	67,849
Due after ten years	612,030
Amortized Cost	1,551,044	$ 1,172,175
Fair Value
Due in one year or less	3,932
Due after one year through five years	18,232
Due after five years through ten years	72,725
Due after ten years	639,008
Fair Value	1,585,348	1,217,852
MBS/CMO
Amortized Cost
Securities without single maturity	704,460
Amortized Cost	704,460	535,526
Fair Value
Securities without single maturity	706,495
Fair Value	706,495	548,307
US Gov't Sponsored Entities & Agencies
Amortized Cost
Securities without single maturity	145,258
Amortized Cost	145,258	88,376
Fair Value
Securities without single maturity	144,956
Fair Value	$ 144,956	$ 88,298

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